Yarn handling apparatus



Dec. 16, 1969 I ET-AL YARN HANDLING APPARATUS Original Filed June 22,1967 w a m m a M Y,

Ill Y4 .4 4 k5 s/ 7 B 4 Wm 3 3 n O W DONALD D. ALDRICH By RICHARD GHILBERT and? A ATTORNEYS 3,484,032 YARN HANDLING APPARATUS Donald D.Aldrich, West Warwick, and Richard G.

Hilbert, Smithfield, RJL, assignors to Leesona Corporation, Warwick, RL,a corporation of Massachusetts Continuation of application Ser. No.648,022, June 22, 1967. This application Jan. 13, 1969, Ser. No. 790,597Int. Cl. B65 17/32, 23/00 US. Cl. 226-97 14 Claims ABSTRACT OF THEDISCLOSURE A guide for an advancing strand of yarn in false twistapparatus. A plurality of the guides direct the strand in a circuitouspath across a plate-type heater. A thin layer of air between a guidegroove surface and the strand of yarn reduces frictional contactsufiiciently so that the twist may pass freely around the guide.

This is a continuation of Ser. No. 648,022 filed June 22, 1967, nowabandoned.

This invention relates to apparatus for guiding a strand of yarn and,more particularly, to guiding a strand of yarn through a false twistmachine in such a manner that the twist may migrate along the strand.

During the operation of conventional false twist machines, acontinuously advancing strand of yarn passes through a twist stop (suchas feed rolls which stop migration of the twist) and a heater (whichheats the yarn to a desired processing temperature), and then through afalse twist spindle (to provide a twist which migrates through thestrand to the twist stop). Then the strand of yarn is wound on a take-upspool. It should be noted that the twist imparted to the advancingstrand of yarn migrates through the yarn. The nature of the process issuch that in order to speed up the passage of the yarn and increasecapacity, the length of the yarn path in the heater must be increased tomaintain the desired processing temperature. This results in lengtheningthe heater and poses a limiting factor in the capacity of commerciallysuccessful false twist equipment.

It has been found commercially impractical to use multipath heaters infalse twist equipment. The reason is that guides pro osed for directingthe advancing strand of yarn through a plurality of passes in the heateract as twist stops in preventing or substantially retarding migration ofthe twist through the strand and back to the intended twist stoppreviously mentioned. Also, many proposed guides are too expensive ormechanically undesirable in the operating environment of a false twistmachine. For example, vibrating guides as well as guide wheels rotatedin a direction opposite the direction of the advancing strand of yarnhave not been found to be industrially adequate.

The invention, in brief, is directed to yarn guides for false twistapparatus in which an advancing strand of yarn is directed by the guidesin a circuitous path through a heater. Frictional contact between theguides and the advancing strand of yarn is effectively reduced byproviding a thin layer of fluid, for example air, therebetween so thatthe twist imparted to the strand of yarn may migrate over the guides.

A primary object of the invention is to provide new and useful yarnguide.

Another object is to provide new and useful yarn guide for yarnprocessing apparatus in which a low frictional contact is maintainedbetween a guide surface and an advancing strand of yarn. A relatedobject is provision for maintaining a thin layer of fluid along theguide nited States Patent surface to provide the low frictional contactwith the advancing strand.

Other objects and advantages of the invention will be apparent from thefollowing descriptions and the drawings in which:

FIG. 1 is a fragmentary, schematic front elevational view of a falsetwist machine with a heater embodying features of the invention;

FIG. 2 is an enlarged fragmentary front elevational view of a portion ofFIG. 1 showing details of a yarn guide;

FIG. 3 is a fragmentary, sectional view taken generally on the line 33in FIG. 2 (and in FIG. 1); and

FIG. 4 is an exploded view of the yarn guide.

Referring to FIG. 1 of the drawings, two false twist assemblies 11 in afalse twist machine 12 are shown. Each assembly includes a supply bobbin13 from which a strand of yarn Y passes through a yarn guide 14 and asuitably twist stop device 15 shown as feed roll ap paratus forcontrolling the tension of the yarn. From the twist stop the yarn passesthrough another yarn guide 16 and into a false twist heater 17 of theplate-type. The strand of yarn passes through a groove 18 in a heatedplate 19 and around a guide 20 where its direction is reversed, thenthrough another heater groove 21 and around a second guide 22 from whichthe strand of yarn passes through a third heater groove 23. From theheater 19, the strand of yarn passes through a false twist spindle 24and traversing mechanism 25 for guiding the yarn onto a driven take-upspool 26.

FIGS. 2 and 3 are enlarged detailed views of an upper one of the guides20 shown in FIG. I, the other guide 22 being identical except fororientation. Each guide includes a porous, hollow, cylindrical guidebody 27 secured in a recess 28 in the heater plate 19 by a special boltor fitting 29 threaded into a coupling 30 which is in turn threaded intoa bore 31 extending through the heater plate. The opposite guide bodyends 32 and 33 are tightly clamped between an annular shoulder 34 on thehead of the bolt 29 and the face of the heater plate recess 28 toprevent escape of air therebetween. A U-shaped groove 35 in the guidebody 27 receives the strand of yarn Y. This guide groove, shown ingreater detail in FIGS. 4 and 5, is shown as annular and it should benoted that the width of the groove between its side surfaces 36 is muchgreater than the diameter of the strand of yarn on the bottom or innersurface 37 of the groove so that any slubs (enlarged portions in theyarn) may pass easily through the groove as the yarn path conformsgenerally to the circular configuration of the inner or bottom surface37 of the groove.

Migration of twist along the yarn Y is assured by low frictional contactprovided between the advancing strand of yarn and the groove surface.Suitable, fluid such as air, and preferably hot air to prevent coolingthe yarn, is supplied through a manifold 38 (FIG. 3) to a tube 39connected with the hollow coupling 30 and then through an axial passage40 in the bolt 29 which communicates with a radial passage 41 openinginto an annular channel 42 in a cylindrical shank portion 43 of thebolt. From the channel 42 the air passes through the porous guide body27 into the guide groove 35 to provide a thin layer of air between theadvancing strand of yarn Y and the surface of the guide groove 35.

The guide body 27 is of a porous material such as sintered aluminum orbronze or preferably stainless steel, or an adequately porous ceramicmaterial. The pores in the body provide passages for the air into theguide groove 35. In order to reduce escape of the air from the guidebody 27, the cylindrical shank 43 has firm sliding engagement with thebore 44 of the guide body. The

opposite ends 32 and 33 of the guide body are in tight engagement withthe face of the heater plate recess 28 and the annular shoulder 34 ofthe bolt 29 to effectively prevent escape of the air through thesepaths. The remaining outer surfaces of the guide body 27, other than thegroove surface, are sealed by a suitable coating or by smearing of theporous surfaces. Desired migration of the twist as the yarn Y movesacross the guide surfaces is assured by an air pressure in the manifold28 in a range of 40 to 50 psi. and a volume of .01 to .02 c.f.m. for 70denier yarn (such as nylon).

Any suitable fluid may provide the layer between the guide surface andthe yarn, and a gas such as air is preferred, in part because ofavailability and ease of handling.

While the invention has been described with particular reference tovarious features and embodiments, additions and changes may be apparentto one skilled in the art.

We claim:

1. Apparatus for guiding an advancing strand of yarn, comprising a guidemount, guide means for guiding the strand through a change in directionand including a guide body having opposite ends and a groove forreceiving said strand, and a bore opening through opposite ends of thebody, means for mounting the guide body on said guide mount andincluding a fitting having a shank extending through said bore in saidguide body, a head on an end of said shank adjacent one of said oppositeends of said body, and a mounting end on said shank opposite said headand releasably secured to said guide mount, means for reducingfrictional contact between the guide body groove and said strand andincluding passage means for the flow of a fluid into said groove, saidpassage means including a passage in said shank having an inlet opening,and a passage in said guide body communicating with the shank passageand said groove for the flow of said fluid from said inlet into saidgroove.

2. Apparatus according to claim 1 in which said guide body is porous andsaid passage in said guide body comprises the pores.

3. Apparatus according to claim 1 in which said guide body is porous andsaid passage in said guide body comprises the pores, and sealing meansfor directing substantially the entire flow of said fluid from saidpassage means into said groove.

4. Apparatus according to claim 3 in which said sealing means comprisesa sealing layer on the surface of said body other than at least aportion of said groove.

5. Apparatus according to claim 1 in which said fitting tightly clampsthe stud head against said one end of said body and the other oppositeend of said body against said mount.

6. Apparatus according to claim 1 in which the mounting end of saidshank is threaded and is threadedly received by said guide mount, theshank passage has a portion which extends axially of said shank andincludes said inlet at the threaded end of the shank, and a transverseportion communicating with the axial portion and opening through theouter periphery of the shank.

7. Apparatus according to claim 6 in which said shank has a channel insaid outer periphery, said channel facing said body and communicatingwith said transverse portion of said shank passage and said passage insaid body.

8. Apparatus according to claim 1 in which said guide mount is a yarnheater, said guide body is porous and said passage in said guide bodycomprises the pores, the mounting end of said shank is threaded and isthreadedly received by said guide mount and tightly clamps the stud headagainst said one end of said body and the other opposite end of saidbody against said mount, said shank engages the surface of the guidebody bore with a snug sliding fit and has a channel in said outerperiphery, said channel facing said porous body, said shank passage hasa portion which extends axially of said shank and includes said inlet atthe threaded end of the shank, and a transverse portion communicatingwith the axial portion and opening into said channel, and means fordirecting substantially the entire flow of said fluid from said passagemeans into said groove.

9. A guide for a strand of yarn, comprising a porous guide body havingopposite ends, a bore opening through said ends, and a strand receivinggroove in the outer surface of said body, and a fitting having a shankextending through said bore, said shank having opposite ends and achannel therebetween facially opposed to said guide body, a head on oneof said opposite ends of said shank, said head being in abuttingrelationship with an adjacent one of said opposite ends of said body, athreaded end on the other of said opposite ends of said shank, saidthreaded end being adapted to be threadedly received by a guide mountfor tightly clamping said guide body between said mount and said head,and said shank having a passage extending between an inlet and saidchannel for the flow of fluid from said inlet through said body and intosaid groove.

10. A guide according to claim 9 in which said guide body has meanscomprising a sealing layer on the surface of said body other than atleast a portion of said groove for directing substantially the entireflow of said fluid from said inlet into said groove.

11. A guide according to claim 9 in which said inlet is at the threadedend of said shank.

12. Apparatus for guiding an advancing strand of yarn and adapted to bemounted on guide mount means comprising, guide means for guiding saidyarn strand through a change in direction and including a guide bodyhaving opposite ends, a groove on said body for receiving said strand,and a bore in said body; means for mounting said guide body on saidguide mount means and including a shank in said bore extending from oneend of said guide body adapted to be attached to said guide mount means;and means for reducing frictional contact between said groove and strandincluding passage means for the flow of fluid into said groove, saidpassage means including a passage in said shank having an inlet openingand further passage means in said guide body communicating with saidshank passage and said groove whereby fluid may be passed from saidinlet opening to said groove to provide a cushion of fluid upon whichsaid strand will ride.

13. Apparatus according to claim 12 wherein said further passage meansin said guide body comprises pores in said guide body.

14. Apparatus according to claim 12 wherein sealing means covers theungrooved portion of said guide body to direct substantially the entireflow of said fluid from said inlet to said groove.

References Cited UNITED STATES PATENTS ALLEN N. KNOWLES, PrimaryExaminer US. Cl. X.R. 226- 196

